"Moonlighting" follows in so many footsteps, it must be a centipede. A centipede with 51 left feet. Cybill Shepherd, whose classy modern western series "The Yellow Rose" failed on NBC, returns in a much more rattly, and motley, vehicle on ABC, premiering as a two-hour movie Sunday night at 9 on Channel 7, then becoming a weekly hour starting Tuesday at 10. Oooo, goody.

As a glamorous model who is defrauded into bankruptcy and reluctantly joins up with a private eye for a new detective career, Shepherd is obviously romping through a field already plowed by "Remington Steele" and "Scarecrow and Mrs. King." The plot of the premiere, meanwhile, has thundering overtones of "Marathon Man": it is about diamonds smuggled into the country after the war, along with the white-haired Nazi who is trying to find them and will stop at the usual nothing to do so. It even opens with a jogging scene.

Shepherd makes herself at home on any screen. Her sexily self-mocking rich-girl purr and cheeky insouciance wear well. Unfortunately, she is teamed with Bruce Willis as the private eye, and he has been directed to emulate the hip cool of contemporary screen heroes like Bill Murray and Eddie Murphy but without any ammunition supplied by the writers, so that he comes off as merely a childish jerk. When a man keels over and crashes to the floor, revealing a back in which a knife has been implanted, Willis cracks, "Hey, that's gotta hurt, fallin' on your nose like that." Larry, Mo and Curly had wittier repartee.

The detective uses expressions like "You gotta be yankin' me" and tells Shepherd "what a cold bitch" she is. In turn, she is saddled with flatulent rejoinders like "Knock that high school locker room grin off your face or I'll knock it off for you." William Powell and Myrna Loy they ain't. The chase for the diamonds ends with Shepherd dangling from a clock's hand a la Harold Lloyd in "Safety Last" and the Nazi dangling from a ledge a la Norman Lloyd in "Saboteur."

We expect television programs to be derivative, but "Moonlighting" doesn't even do its borrowing with finesse. And just as television has reached its quota of soap operas about rich monsters, so has it reached its capacity of fey capers in which people stand around making quips over corpses. It's as if the producers are searching for new ways to desensitize the audience. "Moonlighting" beats a stable full of dead horses.